Matcha Whoopie Pies
- 2 cups flour
- 1/2 cup Dutch-process cocoa powder, such as Droste
- 1 1/2 teaspoons baking soda
- 3/4 teaspoon fine sea salt
- 1/2 cup unsalted butter, at room temperature
- 1 cup packed dark brown sugar
- 1 large egg
- 1 teaspoon vanilla extract
- 1 vanilla bean, split lengthwise and seeds scraped out
- 1 cup buttermilk
- MATCHA FILLING
- 1 1/2 cups powdered sugar
- 1 1/2 tablespoons matcha*
- 3 ounces cream cheese
- 6 tablespoons unsalted butter, at room temperature
- 1. Preheat oven to 350°. Sift flour, cocoa, baking soda, and salt into a medium bowl.
- 2. Beat butter and brown sugar in a large bowl with a mixer on medium speed until very fluffy, 3 to 4 minutes.
- 3. Beat in egg, vanilla extract, and vanilla seeds. Reduce speed to low and gradually add flour mixture; then gradually beat in buttermilk until smooth, scraping down inside of bowl as needed.
- 4. Line 2 large baking sheets with parchment paper or Silpat mats*. Put batter in a piping bag with a large tip (or cut a 1/2-in. corner off a resealable plastic bag and spoon in batter). Form 1-tbsp. mounds of batter 2 in. apart on sheets. Bake about 12 minutes or until cakes spring back when poked. Transfer to rack to cool.
- 5. Meanwhile, make filling: Sift powdered sugar and matcha together into a medium-large bowl. Add cream cheese, butter, and mascarpone and beat with a mixer on low speed at first, then on medium until very smooth and creamy, about 2 to 3 minutes.
- 6. Using an offset spatula or a butter knife, generously spread some filling on the flat side of a cake and top with another cake. Repeat for rest of cakes.
- *Chill matcha after opening to slow oxidation. Silpats (silicone baking mats) prevent sticking.
Note: Make ahead: Cakes, up to 3 days, stored airtight at room temperature between sheets of parchment; filling, up to 2 days, chilled (bring to room temperature before spreading).